In modern agricultural enterprises, animals are almost exclusively milked by means of an automatic milking plant which is essentially composed of a vacuum source, a plurality of teat cups, which are to be applied to the animal's udder, a milk collecting unit, which will also be referred to as milk collecting piece in the following, and a collecting tank. Furthermore, flexible connection lines are provided between the teat cup and the milk collecting piece as well as between the milk collecting piece and the collecting tank. The flexible connection line which is provided between the teat cup and the milk collecting piece and which will be referred to as milk hose hereinbelow is normally subjected to strong loads by kinking and impactlike effects, e.g. when said connection line is trodden on by the personnel or by animals. In order to explain the problems more clearly, a part of a typical automatic milking plant and its mode of operation will be described with reference to FIG. 1.
FIG. 1 shows a milk collecting piece 101 provided with connection elements 102 having each secured thereto a milk hose 104. To make things easier, only one milk hose is shown completely. A teat cup 103 is connected to the milk hose 104 as well, so that a fluid connection is established between the milk collecting piece 101 and the teat cup 103. The milk hose 104 comprises a first end area 105, which is pushed onto a respective connection element (not shown) of the teat cup 103, and a second end area 106, which is pushed onto the connection element 102. The additional components of the automatic milking plant, e.g. the vacuum source, the collecting tank as well as the connection line leading from the milk collecting piece 101 to the collecting tank are not shown for the sake of simplicity.
When the automatic milking plant is in use, in particular when the milking unit is applied and removed as well as during cleaning and transport of the milking unit, the milk hose 104 is constantly subjected to forces in the form of tensile loads and bending strains as well as impact loads. Before and after the milking process, for example, the danger exists that the animal will tread on parts of the milking unit, in particular on the milk hose 104. Furthermore, especially during trans-port of the milking unit, impact loads, which are caused e.g. by neighbouring teat cups and which act on the milk collecting piece 101 and there especially on the connection element 102, will occur more frequently due to the flexible connection between the individual parts, i.e. the teat cups 103 and the milk collecting piece 101. Especially the impact loads occurring when the milking unit is dropped and falls onto the milk hose in the area of the connection element will lead to microperforations in the milk hose and, finally, to a fracture of the milk hose. These impact loads, which occur again and again during daily use, lead, in the final analysis, to a premature wear of the material and consequently to a fracture of the milk hose 104 in the region of the second end area 106. A fracture of the milk hose 104 will not only cause additional costs, but the breaking of the material which, typically, begins gradually can have the effect that milk residues will collect in the second end area 106 for a certain period of time, whereby the quality of the milk will be impaired.
In view of the problems described hereinbefore, it is therefore desirable to provide a suitable device which prevents the negative effect of impact loads on the service life of the milk hose or which at least reduces this effect to a substantial extent.